1. Technical Field
The present invention relates to a lighter employing an ignition system which presents increased difficulty of operation by unintended users, and more particularly, relates to a piezoelectric lighter with such a system.
2. Background Art
Disposable gas lighters are available in a variety of forms. One common element of disposable lighters is an actuator pad or lever used to initiate the flow of fuel. An actuator pad is operated in conjunction with a spark producing mechanism so that the flow of fuel is ignited soon after it commences. For example, lighters employing conventional spark wheels require a user to rotate a toothed spark wheel against a flint in order to generate a spark. The user then depresses the actuator pad, to release gas and produce a flame.
Another means of ignition for disposable lighters employs a piezoelectric mechanism. In this type of ignition mechanism, a piezoelectric element, such as a crystal, is struck by a plexor in order to produce an electric spark. The spark is conducted to a location near the opening of the valve to ignite the gaseous fuel. The actuator pad, upon forced depression by a user, commences both the flow of the fuel and the ignition process. An example of such a piezoelectric ignition mechanism is disclosed in U.S. Pat. No. 5,262,697, entitled xe2x80x9cPiezoelectric Mechanism For Gas Lighters.xe2x80x9d
As with spark wheel ignition mechanisms, measures have been introduced to increase the difficulty of activation to prevent unintended activation of piezoelectric mechanisms or activation by unintended users (e.g., children 5 years old and younger). One typical method is to incorporate a separate latch member disposed under the actuator pad, which inhibits depression of the actuator pad. Examples of such mechanisms are shown in U.S. Pat. Nos. 5,435,719, 5,584,682, and 5,636,979.
There remains, however, a need in the art for improved mechanisms which increase the difficulty of operation unintentionally or by unintended users, and at the same time are user-friendly for intentional operation and intended user.
According to the present invention a lighter resistant to use by unintended users is disclosed. The lighter comprises a lighter body having a fuel compartment, a valve for supplying fuel from the fuel compartment, an actuator, an ignition mechanism, and a latch member. The actuator is mounted for movement with respect to the lighter body. The ignition mechanism includes an actuation axis, and movement of the actuator from a first position to an actuation position occurs along the actuation axis. This movement of the actuator causes the ignition mechanism to ignite the fuel. The latch member is pivotally coupled to the actuator and may extend along a rearward portion of the actuator. When the latch member is in an inoperative position, a portion of the latch member is arranged to limit movement of the actuator along the actuation axis. Upon pivoting the latch member to an operative position, the portion of the latch member is unaligned with the portion of the lighter body, which permits movement of the actuator from the first position to the actuation position to actuate the ignition mechanism to ignite the fuel.
In yet another embodiment the actuator further includes an internal wall that defines a longitudinally extending channel adapted to receive the latch member. In one embodiment, the lighter includes a configuration which prevents removal of the latch member from the actuator channel. This retention in one embodiment is provided by a pair of arms extending from the actuator into the channel. In another embodiment, the retention is provided by a projection on the actuator that contacts a projection on the latch member.
According to one embodiment of the present invention, the actuator and the latch member have cam surfaces for pivotally coupling the latch member to the actuator. According to another embodiment, the latch member and actuator are pivotally coupled by a pin. In another embodiment, the latch member and actuator cooperate to prevent the latch member from over-pivoting. In another embodiment, the lighter further includes a biasing element disposed between the latch member body portion and the actuator for biasing the latch member into the inoperative position. The biasing element is a spring integrally formed with the latch member, a coil spring separate from the latch member or a metal leaf spring coupled to the latch member.